The country is now getting, courtesy of Bert Lance, its first view of Jimmy Carter under pressure. The President turns out to be a lonely man surrounded by an inexperienced staff, who is not exempt from moral blindness and poor judgment.

So the interesting question is not how to ease Lance out. It is how to reorder the administration to ensure better performance the next time the going gets tough.

Lance has been a central figure not because - as his defenders assert - he is good with the business community or the Congress. Still less because he knows how to balance the budget or reorganize the government.

On the contrary, Lance has been important because he is one of the very few persons with whom Carter can talk easily and openly about the whole range of presidential business. He is - as Robert Kennedy was to his brother and Abe Fortas to Lyndon Johnson - a presidential confidant. Only where most Presidents have tended to remove their closest advisers from the White House at least a little, Carter brought Lance into the thick of things as director of the Office of Management and Budget.

One reason was the character of the White House staff. The Georgians at the very heart of the staff - Hamilton Jordan, Jody Powell, Robert Lipshutz, Jack Watson and Stuart Eizenstat - are plain subordinates. They have seen little of the country, and less of the world. Far from being able to question the President's judgment, their stock in trade is believing in the quintessential rightness of Carter instincts.

As it happened, Carter's instincts played him false when it came to Lance. He did nothing to get the facts - he may even have lent himself to a coverup - when the issue arose before the inauguration. He turned a blind eye when leading newspaper and magazines began revealing serious evidence of irregularities in Lance's banking business.

He voiced a ringing vote of confidence in his budget director after a report by the Comptroller of the Currency avoided outright condemnation of Lance only by narrowly circumscribing its focus. He allowed Sens. Abraham Ribicoff and Charles Percy to warm him that they had evidence of wrongdoing that had to be referred to the Department of Justice - and then did nothing.

The President's staff ministered assiduously to his errors. Powell, the press secretary, stood up to reporters for days without knowing what he was talking about. Lipshutz, the White House counsel, saw the Comptroller's report early but failed to insist to the President that it was a condemnation, not an exoneration, of Lance. Jordan first blamed the trouble on Secretary of the Treasury Michael Blumenthal, whose White House standing suffered accordingly.

The Carter administration is going to have to pay dearly for these mistakes. But the experience will not be a total loss if Carter corrects the weaknesses that abetted the trouble. That does not only mean - if Lance has to go - finding a replacement at the OMB. Alice Rivlin of the Congressional Budget Office or former Budget Director Charles Zwick, among others, could fill the vacancy there very well.

The real trick would be finding an across-the-board adviser with whom the President feels comfortable. Perhaps Carter could lean more on Attorney General Griffin Bell or Vice President Walter Mondale or Altanta lawyer Charles Kirbo. But Mondale did not get where he is by talking back, and Bell and Kirbo are ill-placed to shape up the White House staff.

So what is required is a large look at the whole structure of the administration. The President not only needs to bring new strength to his circle of intimates. He also needs to locate that strength centrally so that government becomes more than a field marshal commanding a corporal's guard.